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                        <h2 id="&#x65B0;&#x589E;&#x6570;&#x7EC4;&#x65B9;&#x6CD5;&#x3001;&#x5C5E;&#x6027;&#x8868;&#x8FBE;&#x5F0F;">&#x65B0;&#x589E;&#x6570;&#x7EC4;&#x65B9;&#x6CD5;&#x3001;&#x5C5E;&#x6027;&#x8868;&#x8FBE;&#x5F0F;</h2>
<h4 id="map-&#x65B9;&#x6CD5;">map() &#x65B9;&#x6CD5;</h4>
<p>map&#x65B9;&#x6CD5;&#x53EF;&#x4EE5;&#x5206;&#x522B;&#x5904;&#x7406;&#x6570;&#x7EC4;&#x4E2D;&#x7684;&#x6210;&#x5458;&#xFF0C;&#x8FD4;&#x56DE;&#x4E00;&#x4E2A;&#x65B0;&#x6570;&#x7EC4;&#xFF0C;&#x4E5F;&#x53EF;&#x4EE5;&#x7528;&#x4E8E;&#x904D;&#x5386;&#x6570;&#x7EC4;</p>
<pre><code class="lang-javascript"><span class="hljs-keyword">let</span> aList = [<span class="hljs-string">&apos;a&apos;</span>,<span class="hljs-string">&apos;b&apos;</span>,<span class="hljs-string">&apos;c&apos;</span>];

<span class="hljs-comment">// &#x7B2C;&#x4E00;&#x4E2A;&#x53C2;&#x6570;&#x662F;&#x6570;&#x7EC4;&#x7684;&#x6210;&#x5458;&#x503C;&#xFF0C;&#x7B2C;&#x4E8C;&#x4E2A;&#x53C2;&#x6570;&#x662F;&#x6210;&#x5458;&#x7684;&#x7D22;&#x5F15;&#x503C;</span>
aList.map(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">item,i</span>)</span>{
    alert(i + <span class="hljs-string">&apos; | &apos;</span> + item);
})
</code></pre>
<h4 id="includes-&#x65B9;&#x6CD5;">includes() &#x65B9;&#x6CD5;</h4>
<p>includes&#x65B9;&#x6CD5;&#x8FD4;&#x56DE;&#x4E00;&#x4E2A;&#x5E03;&#x5C14;&#x503C;&#xFF0C;&#x8868;&#x793A;&#x67D0;&#x4E2A;&#x6570;&#x7EC4;&#x662F;&#x5426;&#x5305;&#x542B;&#x7ED9;&#x5B9A;&#x7684;&#x503C;</p>
<pre><code class="lang-javascript">[<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>].includes(<span class="hljs-number">2</span>)     <span class="hljs-comment">// true</span>
[<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>].includes(<span class="hljs-number">4</span>)     <span class="hljs-comment">// false</span>
[<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-literal">NaN</span>].includes(<span class="hljs-literal">NaN</span>) <span class="hljs-comment">// true</span>
</code></pre>
<h4 id="filter-&#x65B9;&#x6CD5;">filter() &#x65B9;&#x6CD5;</h4>
<p>&#x548C;map&#x7C7B;&#x4F3C;&#xFF0C;filter&#x65B9;&#x6CD5;&#x63A5;&#x6536;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x3002;&#x4F46;&#x662F;&#x548C;map&#x4E0D;&#x540C;&#x7684;&#x662F;&#xFF0C; filter&#x628A;&#x4F20;&#x5165;&#x7684;&#x51FD;&#x6570;&#x4F9D;&#x6B21;&#x4F5C;&#x7528;&#x4E8E;&#x6BCF;&#x4E2A;&#x5143;&#x7D20;&#xFF0C;&#x7136;&#x540E;&#x6839;&#x636E;&#x8FD4;&#x56DE;&#x503C;&#x662F; true &#x8FD8;&#x662F;false&#x51B3;&#x5B9A;&#x4FDD;&#x7559;&#x8FD8;&#x662F;&#x4E22;&#x5F03;&#x8BE5;&#x5143;&#x7D20;&#x3002;</p>
<pre><code class="lang-javascript"><span class="hljs-keyword">let</span> aList01 = [<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">4</span>, <span class="hljs-number">5</span>, <span class="hljs-number">6</span>, <span class="hljs-number">9</span>, <span class="hljs-number">10</span>, <span class="hljs-number">15</span>];
<span class="hljs-keyword">let</span> aList02 = aList01.filter(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">x</span>) </span>{
    <span class="hljs-keyword">return</span> x % <span class="hljs-number">2</span> !== <span class="hljs-number">0</span>; 
});
alert(aList02); <span class="hljs-comment">// 1, 5, 9, 15</span>
</code></pre>
<h4 id="find-&#x65B9;&#x6CD5;">find() &#x65B9;&#x6CD5;</h4>
<p>&#x8BE5;&#x65B9;&#x6CD5;&#x4E3B;&#x8981;&#x5E94;&#x7528;&#x4E8E;&#x67E5;&#x627E;&#x7B2C;&#x4E00;&#x4E2A;&#x7B26;&#x5408;&#x6761;&#x4EF6;&#x7684;&#x6570;&#x7EC4;&#x5143;&#x7D20;&#x3002;&#x5B83;&#x7684;&#x53C2;&#x6570;&#x662F;&#x4E00;&#x4E2A;&#x56DE;&#x8C03;&#x51FD;&#x6570;&#x3002;&#x5728;&#x56DE;&#x8C03;&#x51FD;&#x6570;&#x4E2D;&#x53EF;&#x4EE5;&#x5199;&#x4F60;&#x8981;&#x67E5;&#x627E;&#x5143;&#x7D20;&#x7684;&#x6761;&#x4EF6;&#xFF0C;&#x5F53;&#x6761;&#x4EF6;&#x6210;&#x7ACB;&#x4E3A;true&#x65F6;&#xFF0C;&#x8FD4;&#x56DE;&#x8BE5;&#x5143;&#x7D20;&#x3002;&#x5982;&#x679C;&#x6CA1;&#x6709;&#x7B26;&#x5408;&#x6761;&#x4EF6;&#x7684;&#x5143;&#x7D20;&#xFF0C;&#x8FD4;&#x56DE;&#x503C;&#x4E3A;undefined&#x3002;</p>
<pre><code>const myArr=[1,2,3,4,5,6];
var v=myArr.find(value=&gt;value&gt;4);
console.log(v);// 5
</code></pre><h4 id="&#x6269;&#x5C55;&#x8FD0;&#x7B97;&#x7B26;">&#x6269;&#x5C55;&#x8FD0;&#x7B97;&#x7B26;(...)</h4>
<p>&#x6269;&#x5C55;&#x8FD0;&#x7B97;&#x7B26;&#xFF08;...&#xFF09;&#xFF0C;&#x5B83;&#x7528;&#x4E8E;&#x628A;&#x4E00;&#x4E2A;&#x6570;&#x7EC4;&#x8F6C;&#x5316;&#x4E3A;&#x7528;&#x9017;&#x53F7;&#x5206;&#x9694;&#x7684;&#x53C2;&#x6570;&#x5E8F;&#x5217;</p>
<pre><code class="lang-javascript"><span class="hljs-keyword">let</span> arr = [<span class="hljs-number">1</span>,<span class="hljs-number">2</span>,<span class="hljs-number">3</span>];
<span class="hljs-keyword">let</span> arr2 = [...arr,<span class="hljs-number">4</span>];
<span class="hljs-built_in">console</span>.log(arr2)  <span class="hljs-comment">// [1,2,3,4]</span>
</code></pre>
<h4 id="&#x5C5E;&#x6027;&#x540D;&#x8868;&#x8FBE;&#x5F0F;">&#x5C5E;&#x6027;&#x540D;&#x8868;&#x8FBE;&#x5F0F;</h4>
<p>&#x5BF9;&#x8C61;&#x7684;&#x5C5E;&#x6027;&#x540D;&#x53EF;&#x4EE5;&#x901A;&#x8FC7;&#x4E2D;&#x62EC;&#x53F7;&#x5199;&#x6210;&#x503C;&#x6216;&#x8005;&#x53D8;&#x91CF;&#x7684;&#x5F62;&#x5F0F;&#xFF1A;</p>
<pre><code class="lang-javascript"><span class="hljs-keyword">let</span> propKey = <span class="hljs-string">&apos;foo&apos;</span>;
<span class="hljs-keyword">let</span> obj = {
  [propKey]: <span class="hljs-literal">true</span>,
  [<span class="hljs-string">&apos;a&apos;</span> + <span class="hljs-string">&apos;bc&apos;</span>]: <span class="hljs-number">123</span>
};
alert(obj.foo); <span class="hljs-comment">// true</span>
alert(obj.abc); <span class="hljs-comment">// 123</span>
</code></pre>

                    
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